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A sensitive and selective high-performance capillary electrophoresis (HPCE) procedure was developed for the determination of total cicletanine in human plasma. The procedure consisted in extraction of the drug with diethyl ether and analysis by micellar electrokinetic capillary chromatography in a fused-silica capillary using sodium dodecyl sulphate in the run buffers and ultraviolet detection. The concentrations of cicletanine obtained by this method were compared with those obtained by a high-performance liquid chromatographic (HPLC) method used routinely. The within-run precision of the methods, expressed as relative standard deviation, ranged from 1.6 to 7.8% for HPLC and from 6.4 to 11.1% for HPCE. Both methods showed an adequate level of accuracy; the relative errors ranged from 0.02 to 3.25% for HPLC and from 0.21 to 2.90% for HPCE. The HPCE method required less than half the time taken by the HPLC method, making HPCE a useful alternative technique for the routine determination of cicletanine in plasma. Both methods were used to follow the time course of total cicletanine in human plasma after a single oral therapeutic dose of the drug. 相似文献
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氨基酸的分析方法及其应用进展 总被引:35,自引:0,他引:35
从衍生试剂角度,介绍了不同衍生化氨基酸的分析方法,包括离子交换色谱法、高效液相色谱法、气相谱法和毛细管电泳法,以及无需衍生化的直接分析法高效阴离子交换色谱-积分脉冲安培法,并总结了蛋白质、食品和生理体液样品中的氨基酸分析方法。 相似文献
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Two methods, capillary electrophoresis (CE) and high-performance liquid chromatography (HPLC), for analysis of cetirizine dihydrochloride in small sample volumes of human plasma were compared. The CE and HPLC assays were developed and validated by analyzing a series of plasma samples containing cetirizine dihydrochloride in different concentrations using these two methods. The extraction procedure is simple and no complicated purification steps or derivatization are required. The analysis time in the HPLC method was shorter than that in the CE method, but solvent consumption was considerably lower in the CE method. The calibration curve was linear to at least 10-1000 ng/mL both for CE and HPLC with r(2) = 0.9993 and r(2) = 0.9994, respectively. The detection limits for cetirizine dihydrochloride were 3 and 5 ng/mL with CE and HPLC (a UV detector was applied in the both cases), respectively. Both methods were selective, robust and specific, allowing reliable quantification of cetirizine dihydrochloride, and could be useful for clinical and biomedical investigations. 相似文献
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Capillary electrophoresis frontal analysis: principles and applications for the study of drug-plasma protein binding 总被引:2,自引:0,他引:2
Capillary electrophoresis is a well-established technique for the study of noncovalent interactions. Various approaches exist and capillary electrophoresis-frontal analysis provides an interesting alternative to the migration shift affinity capillary electrophoresis methods and conventional methods. The present work reviews the principles on which the frontal analysis method is founded. Advantages and limitations of capillary electrophoresis frontal analysis in comparison with both conventional and other capillary electrophoresis based methods for quantification of binding interactions are discussed. Investigations utilizing capillary electrophoresis-frontal analysis have focused on the interaction of drugs with plasma proteins. These studies, primarily addressing the binding of drugs to human serum albumin, alpha1-acid glycoprotein, and lipoproteins are reviewed together with some recent developments in capillary electrophoresis-frontal analysis methodology. 相似文献
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Summary The resolution of chiral drugs, metabolites and related substances continues to be an important area in pharmaceutical analysis.
Two methods for the optical purity testing of (R)-(-)-terbutaline were developed, namely capillary electrophoresis using hydroxypropyl-β-cyclodextrin
and high-performance liquid chromatography using a chiral stationary phase. Validation data such as linearity, recovery, detection
limit, and precision of the two methods are presented. The detection limit of (S)-terbutaline in (R)-terbutaline was 0.05%
by the HPLC method and 0.03% by the CE method. The was generally good agreement between the HPLC and CE results. These methods
were found to be applicable as a practical quality control method for the enantiomeric purity determination of(R)-terbutaline. 相似文献
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We describe two methods for the analysis of oligosaccharide chains in glycoproteins by high-performance liquid chromatography (HPLC) and high-performance capillary electrophoresis (HPCE).O-andN-glycosidically linked oligosaccharides released from glycoproteins can be identified as their borohydride-reduced forms by anion-exchange HPLC with pulsed amperometric detection.N-Glycosidically linked oligosaccharides can also be analyzed as 2-aminopyridine derivatives by HPCE in direct zone electrophoresis mode in an acidic phosphate buffer and zone electrophoresis mode as borate complexes in an alkaline buffer. We also present a convenient procedure for the analysis of the constituent monosaccharides of these oligosaccharides chains by HPLC based on reversed-phase partition mode as 1-phenyl-3-methyl-5-pyrazolone derivatives. 相似文献
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A reversed-phase HPLC method for the analysis of degradation products of the model aspartyl tripeptides Phe-Asp-GlyNH2 and Gly-Asp-PheNH2 after incubation at pH 2 and 10 was developed. Most of the compounds could be separated with a gradient of acetonitrile in water containing 0.1% trifluoroacetic acid. Resolution of the isomeric pairs L-Phe-alpha-L-Asp-GlyNH2/L-Phe-beta-L-Asp-GlyNH2 and L-Phe-alpha-D-Asp-GlyOH/L-Phe-beta-D-Asp-GlyOH was achieved with a gradient of acetonitrile in phosphate buffer, pH 5.0. Under acidic conditions the major degradation pathway was cleavage of the peptide backbone amide bonds yielding dipeptides and amino acids, C-terminal deamidation as well as formation of succidinimyl peptides. At alkaline pH both deamidation of the C-terminal amide as well as isomerization and concomitant enantiomerization of Asp were observed. The peaks were identified both by reference substances and by online electrospray mass spectrometry. The results were compared to a previous developed capillary electrophoresis method. Diastereomeric pairs ofpeptides that could not be separated by capillary electrophoresis were resolved by HPLC while the separation of corresponding pairs of alpha- and beta-Asp peptides was not always achieved by HPLC in contrast to capillary electrophoresis illustrating that both techniques can be complimentary in peptide analysis. 相似文献
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A two-dimensional liquid chromatography/capillary electrophoresis technique was developed for rapid and comprehensive mapping of cell extracts. The cell extracts were first separated by reversed-phase HPLC based on hydrophobicity. Fractions of the effluent from the HPLC system were collected into 96-well microtiter plates and dried under vacuum. The fractions were reconstituted with deionized water, separated by capillary array electrophoresis based on charge-to-size ratio, and detected by UV absorption at 214 nm. Prior to analysis by multiplexed capillary electrophoresis, the reconstituted fractions were concentrated on-column using large volume sample stacking with polarity switching. In this way, high-resolution analysis of even the minor components in the complicated mixture was possible. 相似文献
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砷的形态分析方法研究进展 总被引:14,自引:1,他引:13
对近年有关砷的形态分析的进展作了综述。对新的分离方法,如毛细管电泳法、氢化物发生法及高效液相色谱法给予了较多的注意,还对各种测定方法作了对比和讨论(引述文献79篇)。 相似文献
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McCalley DV 《Journal of chromatography. A》2002,967(1):1-19
The Cinchona alkaloids, which include the pharmaceuticals quinine and quinidine, continue to have a wide variety of important uses. A number of different chromatographic procedures have been developed for the qualitative and quantitative analysis of these compounds in a variety of sample matrices. Reversed-phase HPLC using ODS columns in combination with acidic mobile phases, and UV detection, is the most widely used method. Nevertheless, precautions need to be taken due to the strong silanophilic interactions which can occur with these analytes and the column surface, which can lead to poor peak shape and resolution. Different selectivity may be achieved in HPLC separations by use of alternative stationary phases, or by varying mobile phase pH. The specificity of detection systems may be improved by use of photodiode array UV detectors, or especially mass spectrometers. Thin-layer chromatography (TLC) provides a cheap alternative analytical method, which is especially useful for qualitative analysis. High-performance TLC, gas chromatography, capillary electrophoresis and capillary electrochromatography are all methods which after some development, could prove useful for Cinchona alkaloid separations. 相似文献
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A method for the determination of the major components of (methoxymethyl)melamine resins, with quantitative analysis of unreacted melamine by capillary zone electrophoresis (CZE) using electrospray ionization-mass spectrometry (ESI-MS) is presented. Using a low background electrolyte (BGE) pH, components are separated according to their charge/ionic radius ratio with a distinctly different separation selectivity compared to the HPLC methods commonly employed in melamine-resin analysis. The use of a time-of-flight mass spectrometer (TOF-MS) was concluded to be necessary, as the complex samples studied required maximum sensitivity and resolution, which is clearly superior for TOF-MS detectors over their quadrupole counterparts. A standard curve of free melamine was determined with an R(2) = 0.999 over a concentration range of an order of magnitude. This method offers the unique separation selectivity of CZE as well as a quicker analysis time, especially for dimers compared to the HPLC methods used to date. 相似文献
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对从1979年至2005年期间植物皂甙的测定方法的进展作了评述。内容主要涉及薄层色谱法、气相色谱法、高效液相色谱法(HPLC)、HPLC与其他方法联用及毛细管电泳等,引用文献35篇。 相似文献
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This article gives an overview of the applications of capillary electrophoretic methods to investigate the non‐covalent interactions of peptides (peptide complexes) with variable middle‐ and high‐molecular‐mass receptors (ligands) as well as with small ions and molecules in the period 2007–2014. Different modes of capillary electrophoretic methods, such as mobility shift (vacancy) affinity capillary electrophoresis, multiple injection affinity capillary electrophoresis, partial filling affinity capillary electrophoresis, Hummel–Dryer method, vacancy peak method and (continuous) frontal analysis capillary electrophoresis, are briefly described and their applicability to determination of binding constants of peptide complexes is discussed. In addition, the detailed experimental conditions of individual applications and the values of binding constants of the particular peptide complexes are presented. 相似文献
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A simple capillary zone electrophoresis method has been developed for the separation of polyethylene glycols (PEGs) consisting of differing amounts of polymers with different monomer numbers up to an average molecular mass of 1500. To provide both charge and detectability, the analytes were derivatized with phthalic anhydride according to a conventional method and a newly developed microwave-assisted method. While obtaining nearly equal amounts of single and double esterificated PEGs with the conventional method, the fraction of single derivatized PEGs is considerably reduced by microwave-assisted reaction. In order to compare the capillary zone electrophoresis results, an HPLC method with evaporative light scattering detection has been established. This method was successfully applied to the analysis of underivatized PEG 400, 1000 and 1500. 相似文献
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How experimental design can improve the validation process. Studies in pharmaceutical analysis 总被引:2,自引:0,他引:2
Furlanetto S Orlandini S Mura P Sergent M Pinzauti S 《Analytical and bioanalytical chemistry》2003,377(5):937-944
A critical discussion about the possibility of improving the method validation process by means of experimental design is presented. The reported multivariate strategies concern the evaluation of the performance parameters robustness and intermediate precision, and the optimisation of bias and repeatability. In particular, accuracy and precision improvement constitutes a special subset of experimental design in which the bias and the relative standard deviation of the assay are optimised. D-optimal design was used in order to plan experiments for this aim. The analytical methods considered were capillary electrophoresis, HPLC, adsorptive stripping voltammetry and differential pulse polarography. All methods were applied to real pharmaceutical analysis problems. 相似文献